Faces from the Ice Age
Photoshop B.C. Edition writes: "Talk about data mining. Apparently some of those ice age cave paintings found throughout France actually may have, or had, some human portraits engraved, not on their walls, but on their floors. The controversial discovery was made at the Lascaux cave complex whose paintings date back around 15,000 years ago. This may explain why all the previous examples of cave paintings never depicted realistic representations of humans, while at the same time successfully representing realistic looking animals. (By the way, the one at the bottom of the article looks like Darth Maul ;)"
I think you need a time machine to know for sure, but I'd like to hear the basis of your dating anyway!